1. Field of the Invention
The present invention relates to a disc drive suspension incorporated in an information processing apparatus such as a personal computer.
2. Description of the Related Art
FIG. 15 shows a part of a hard disc drive (HDD). This disc drive comprises suspensions 3 and actuator arms 4 on which the suspensions 3 are mounted, individually. Each suspension 3 supports a magnetic head portion 2 for recording information on or reading it from the recording surface of a disc 1 for use as a recording medium. The actuator arms 4 are turned around a shaft (not shown) by means of a positioning motor (not shown).
Each suspension 3 is provided with a base plate 5, a load beam 6 extending from the base plate 5 toward the head portion 2, a flexure 7, etc. A proximal portion 6a of the load beam 6 is lapped and fixed on the base plate 5. The flexure 7 is fixed on the load beam 6 by laser welding. A slider 8 that constitutes the head portion 2 is mounted on the distal end portion of the flexure 7.
A suspension in which a load beam and a base plate are coupled to each other by means of a hinge member has been developed as an alternative form. This hinge member has an end portion lapped and fixed on the proximal portion of the load beam, a base plate mounting portion lapped and fixed on the base plate by laser spot welding or the like, and elastically deformable flexible portions formed between the end portion and the base plate mounting portion.
If the hinge member and the base plate are fixed on each other in a plurality of positions by laser spot welding, the load beam may easily flutter (or its distal end portion may waver in its width direction), depending on the laser weld positions. Thus, it was found that the flutter characteristic of this suspension should be improved.
Accordingly, the object of the present invention is to provide a disc drive suspension provided with a hinge member capable of improving its flutter characteristic.
The present invention is applicable to a suspension that comprises a Load beam, a base plate, and a hinge member. The hinge member has an end portion lapped and fixed on the proximal portion of the load beam, a base plate mounting portion lapped and fixed on the base plate, and flexible portions elastically deformable in the thickness direction thereof and situated individually on the opposite sides of an opening formed between the end portion and the base plate mounting portion. The hinge member and an end portion of the base plate are fixed to each other by means of laser welds in positions near the flexible portions, and the laser welds are formed individually on at least two spots in each of regions extending in the axial direction of the hinge member from the flexible portions.
According to this invention, the flutter characteristic and performance of the suspension that has the base plate and the hinge member fixed by laser spot welding can be improved.
Preferably, the laser welds should be formed individually in three positions corresponding to the vertices of a triangle in the region near each of the flexible portions of the hinge member, two of the three laser welds being arranged side by side in the width direction of the hinge member. According to this invention, the flutter characteristic can be improved further.
Furthermore, the laser welds may be formed individually in three positions near each of the flexible portions of the hinge member so as to be arranged side by side in the width direction of the hinge member. According to this invention, the flutter characteristic can also be improved.
Additional objects and advantages of the invention will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. The objects and advantages of the invention may be realized and obtained by means of the instrumentalities and combinations particularly pointed out hereinafter.